Ello there,

I'm trying to over clock my 4870 but not having a terrible amount of luck atm. Using Vista X64 so programs like ATITool and Riva don't work, for daft reasons. Therefore i have no choice but to use ATI Overdrive, built into the CCC.

Firstly my GPU clock doesn't go above 800 and my memory clock wont go above 1100. Secondly, I can max my GPU clock out with no problems, it isn't even getting that hot under full load but my memory clock wont go above 1000, when it does, the screen fills with black and coloured squares.

Can anyone give me some tips.

Go here and d/l GPU-Z (allows you to save current BIOS) and BIOS editor 1.18 (lets you edit BIOS, for example, you wanna be upping limits for core clock).

Once you have a BIOS:

Make a bootable USB drive details here software under method 2.

Download ATIFlash and read docs supplied which will give you flash string.

Job done

Most I could get mine to was 820 and 1080 with CCC. Wasn`t worth it IMO for a few extra fps, it`s so damn good at stock

RivaTuner works as long as you confirm "Yes" to 'download updates?' when it installs.

jus set the max core clock and use memory speed of 995 then up the fan speed when playing games! You shouldnt notice any real in game difference with higher clocks. Easiest method!